An integrated circuit containing digital metal oxide semiconductor (MOS) transistors and analog MOS transistors is fabricated to provide low off-state currents in the digital MOS transistors using halo implants to form halo regions which limit the lateral extents of drain extensions, referred to as lightly doped drain (LDD) regions, under the gates of the digital MOS transistors. The halo regions have an opposite conductivity type from the LDD regions. The analog MOS transistors require uniform threshold voltages, which can be achieved by forming larger LDD regions compared to the digital MOS transistors and by not laterally limiting the larger LDD regions with halo regions under the gates of the analog MOS transistors. However, fabricating the analog MOS transistors with dedicated implants undesirably increases fabrication cost and complexity of the integrated circuit.